Green Cloud Computing : Techniques every QA should know It's important for QA practitioners to take a look at green computing and employ its techniques in quality assurance practices

Cloud computing offers immense potential for resilience, scalability and an array of services useful to every quality assurance practitioner. Most cloud computing techniques offer cloud-based platforms/services that are helpful in ensuring a requisite set of quality attributes, while quality enabler tools such as reporting/monitoring suites, testing tools, verification frameworks may also need to be brought in to the cloud in order to assess target quality aspects. Though ICT technologies like cloud computing are being used by QA testers worldwide, their evolution has affected the environment negatively, forcing engineers to find ways to create eco-friendly technologies. It's important, therefore, for QA practitioners to take a look at green computing and employ its techniques in quality assurance practices.

What is green cloud computing?

Green computing treats different aspects related to energy consumption such as computer devices, lighting energy, cooling system, networks energy consumption etc. Green Computing refers to the efficient use of computers and other technologies while respecting the environment through energy efficient peripherals, improved resources use and reduced electronic waste. These goals will not only make the resources more efficient but will also enhance the overall performance. It typically has two aspects:

• Software technology: the objective is to develop methods that help in attaining efficiency, storage and energy
  
• Hardware aspect: the purpose is to provide technologies which can not only minimize the consumption of energy but also make it economically efficient with the help of recycling

Modern QA practices host multiple applications, ranging from those that run for a few seconds to those that run for longer periods of time on collective hardware platforms. The need to manage multiple applications creates the challenge of on-demand reserve provisioning and allocation in response to time-varying workloads. QA practitioners following the green computing trend will not only reduce Co2 emissions, but they will also reduce the amount of energy used and any amount of saving will result in huge benefits in energy consumption globally.

Green Cloud Computing Techniques for QA Testers

Energy efficiency for green cloud computing from a QA tester's perspective can be achieved by finding the most efficient way of energy use and using clean energy. Energy management in the cloud's servers or using an auto-scaling infrastructure can reduce energy consumption. Cloud computing also allows energy efficiency through its virtualisation feature. These techniques are designed to be the most energy efficient they can be from all aspects, such as lightning, electrical, mechanical and computer systems. To reduce energy consumption, a number of hardware and software optimisations can be made by a quality assurance practitioner:

• Hardware includes all the information and communication technology in the data centre, such as network and servers. They are a central part of the data centre since they perform the main tasks. Hardware also includes cooling equipment, lighting the power supply and the building itself.
  
• Software represents everything that runs on top of the ICT equipment: it includes Cloud Management Systems (CMS) that are in charge of managing the data centre. It also includes appliances that represent the software used by the user. Energy consumption can be minimised at the server level by using specific techniques in the compiler layer; the operational layer and the application layer such as powering off part of the chips, making the CPU clock speed slower; working on improving the performance per watt; increasing the efficiency of workload management; and powering off the idle components.

Green computing can be achieved through four parts: hardware device manufacturing, software techniques, people awareness, and standard policies. Some useful green cloud computing techniques are:

Virtualisation: Virtualisation is the technology in cloud computing that enables virtual machines management and energy efficiency through better resource sharing. It allows the sharing of physical resources and maximises the efficiency of resource utilisation and improves the availability of the service through dynamic migration. It enables the execution of multiple operating system instances through the hypervisor. These instances are called virtual machines and run on the same physical server with a dedicated operating system and hosted testing applications. Virtualisation enables the ability to attain higher hardware utilisation rates and reduces costs by accumulating a number of physical servers into a single server.

Dynamic Voltage and Frequency Scaling: Dynamic Voltage and Frequency Scaling (DVFS) enables scheduling to minimise power consumption and increase performance. This method is based on a clock being related to electronic circuits; its operating frequency is synchronised with the supply voltage but its power savings are low compared to other approaches. DVFS enables processors to run at different combinations of frequencies with voltage to reduce the consumption of the processor's power.

Nano Data Centres: Nano data centre is a distributed computing platform, which is preferred to modern typical data centres for its low energy consumption. It is based on the idea of having a big number of data centres in smaller sizes than usual, distributed geographically and interconnected instead of the typical data centres that are large in size and lesser in number, with a consumption of up to 30 per cent more energy.

Thus, in a testing environment where the data centres and servers are remotely controlled under the cloud computing models, there is a need for green computing to make these more energy efficient and economically reliable. The different ways discussed above will be helpful for QA testers to get involved in sustainability through cloud computing techniques and to make the cloud greener.